package com.heima.kafka;

import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.junit.Test;

import java.time.Duration;
import java.util.Collections;
import java.util.Properties;

public class ConsumerQuickStart {
    @Test
    public void getMsg(){
        //1.添加kafka的配置信息
        Properties properties = new Properties();
        //kafka的连接地址
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "120.27.213.138:9092");
        //消费者组
        properties.put(ConsumerConfig.GROUP_ID_CONFIG,"group1");

        //消息的反序列化器
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");

        //消费者对象
        KafkaConsumer<String, String> consumer = new KafkaConsumer<>(properties);
        //3.订阅主题
        consumer.subscribe(Collections.singletonList("itheima-topic"));
        //当前线程一直处于监听状态
        try {
            while (true){
                //4.获取消息
                ConsumerRecords<String, String> consumerRecords = consumer.poll(Duration.ofMillis(1000));
                for (ConsumerRecord<String, String> consumerRecord : consumerRecords) {
                    System.out.println(consumerRecord.key());
                    System.out.println(consumerRecord.value());
                }
                consumer.commitAsync();
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("记录错误信息"+e);
        }finally {
            try {
                consumer.commitSync();
            }finally {
                consumer.close();
            }
        }

    }
}
